Determination of particulate phase polycyclic aromatic hydrocarbons and their nitrated and oxygenated derivatives using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry.

An analytical method has been developed for the quantitative determination of polycyclic aromatic hydrocarbons (PAHs) and their nitrated and oxygenated derivatives (nitro- and oxy-PAHs respectively) in particulate matter (PM) samples. The sample preparation procedure included only a simple and quick sonication-assisted extraction step, clean-up based on addition of water and centrifugation as well as pre-concentration under N stream. The determination of 16 PAHs and 4 oxy-PAHs was carried out by gas chromatography-mass spectrometry, while liquid chromatography-tandem mass spectrometry was used in the case of the 11 investigated nitro-PAHs. The optimized method was fully evaluated in terms of trueness, precision (repeatability), limit of detection (LOD), limit of quantification (LOQ), sensitivity and linearity. The LOQ values ranged at pgm level for the investigated PAHs (42pgm), oxy-PAHs (either 42 or 83pgm) and nitro-PAHs (either 83 or 167pgm) as well. The developed method was applied for the quantitative determination of PAHs, nitro- and oxy-PAHs in urban PM (particles with aerodynamic diameter smaller than 2.5μm) samples (n=36) collected in Budapest, Hungary. Almost 100% of the PM samples contained the investigated PAHs and oxy-PAHs in detectable and quantifiable amounts; however, the concentration of the nitro-PAHs was generally lower than the corresponding LOD/LOQ values. According to our results, during the 3-year long sampling campaign the concentration of benzo(a)pyrene never exceeded the limit value (1ngm) set by the European Commission.